A large Swedish study finds a link between fruit and vegetable consumption and lifespan. People who ate fewer than the recommended "5 a Day" portions of fruit and vegetables tended not to live as long as people who ate 5 portions a day or more, say the researchers.
Alicia Wolk, Professor of Nutrition Epidemiology at the Karolinska Institute in Stockholm, and colleagues found no additional benefit, in terms of more years of life, in consuming more than 5 a day.
They write about their findings in the August print issue of the American Journal of Clinical Nutrition.
In their background information, the authors explain that not many large studies have looked at the link between fruit and vegetable consumption and lifespan (as opposed to the many that have examined links with health and disease).
And where studies have looked at lifespan links to fruit and vegetable intake, the results are somewhat inconsistent.
For their study, they looked at the relationship between different amounts of daily fruit and vegetable consumption and timing and rate of deaths in a large population of 71,706 Swedish men and women who completed questionnaires about their food intake as participants in the Swedish Mammography Cohort and the Cohort of Swedish Men.
Large 13-year study
The participants, who were followed for 13 years, were aged from 45 to 83, and about half were men. During the follow-up, just under 11,500 of the men and women died.
When they analyzed the results, the researchers found that eating fewer than 5 servings of fruit and vegetables a day was progressively linked to shorter lifespan and higher rates of death in the men and women, compared with those who ate 5 or more a day.
Thus, the less fruits and vegetables they ate under the 5 a day threshold, the shorter their lives.
Those who said they never ate fruit and vegetables had lives cut short by an average of 3 years, and were 53% more likely to die during the follow-up, compared with those who said they ate 5 servings a day or more.
The study was not designed to look for cause and effect, so it cannot say for sure that eating fruits and and vegetables actually increases lifespan. The cause could be due to other factors that differed between those who ate fruits and vegetables and those who did not.
Participants who said they ate fewer fruits and vegetables tended to be smokers, with fewer years of education, and bigger eaters of red meat, high-fat dairy goods, snacks and sweets.
But in contrast, those who ate a lot of fruits and vegetables tended to consume more calories, says Wolk in a report on the study by Reuters Health.
However, when the team adjusted the results to take into account possible effects of gender, BMI (body mass index), exercise, alcohol and smoking, this did not change the results very much.
When they looked at fruit and vegatable consumption separately, Wolk and colleagues found those who never ate fruit lived on average 19 months less than those who ate one portion of fruit per day.
And those who said they ate three servings of vegetables per day lived 32 months longer than those who said they never ate vegetables.
Wolk says most experts tend to discuss the effect of fruit and vegetables combined, but she told Reuters Health that when she speaks to lay people she says "eat vegetables more than fruit, but eat both."
Fruits and vegetables differ in the vitamins they contain, and vegetables tend to be lower in calories, says Wolk.
The World Health Organization (WHO) recommends a minimum of 400g of fruit and vegetables a day for adults.
In the UK, where a 2012 poll suggests that only one in five Britons consumes the recommended "5 a day," health authorities encourage people to think of their 400g a day of fruit and veg in 5 portions of 80g each. This would constitute for example, half a fresh grapefruit, two dried figs, eight cauliflower florets, three heaped tablespoons of baked beans and an apple.